| 摘要 |
<p>A Navigation Aid comprising three transparent members being, (a) A ground speed member bearing a ground speed scale (b) A transparent true air speed member bearing a true air speed scale and (c) A wind speed and direction member bearing a wind speed scale and a wind direction indicator, the ground speed member bearing about the origin of its scale a compass rose which defines a drift scale which measures the angle between the ground speed scale and the true air speed scale, the three members lying in parallel juxtaposed planes and the true air speed member and the ground speed member being connected together at the origins of their scales by a connection having one rotational degree of freedom, the wind speed and direction member being connected to the true air speed member at the origin of its scale by a connection having one translational degree of freedom and one rotational degree of freedom.</p> |
